Solid Waste Disposal Area Research Articles

A solid waste disposal site selection procedure based on groundwater vulnerability mapping

In this study, a new, GIS-based solid waste site selection tool (DUPIT) is introduced to obtain a systematic and unbiased methodology during the evaluation phases of alternative solid waste disposal areas with regards to vulnerability to groundwater pollution. The proposed tool is an index technique based on the linear combination of five different hydrogeological parameters including Depth to groundwater table, Upper layer lithology, Permeability of the unsaturated zone, Impermeable layer thickness and Topographic slope. Five different categories are developed to classify each alternative based on the suitability of the site for a solid waste disposal area. As a result, each site is ranked according to the contamination risks for groundwater resources. The proposed technique is applied to the District of Torbali near Izmir, Turkey to determine the most appropriate solid waste disposal site location. The Torbali application is implemented by using a GIS database developed for the area. Based on the results of this application, the best alternative solid waste disposal site for Torbali is selected to be located in the northern portions of the city where the groundwater table is deep, the permeability is low and the topographic slope is mild.

Non-inert industrial solid waste disposal in landfill dumps: evaluation of toxicity and implications for the environment and human health

According to Brazilian recommended technical procedures (mainly NBR 10,004), solid waste must be previously classified in order to be disposed of adequately. Non-inert industrial solid waste is being dumped in landfill areas, most of which operate inefficiently and are located near the population and important ecosystems. In order to evaluate the potential toxicity of solid waste produced by various types of industries, 21 samples were analyzed according to NBR 10,004 procedures. Of these, 18 were classified as non-inert solid waste. The main substances contributing to the classification of these samples as non-inert waste were: aluminum, iron, manganese, phenol, and surfactants. Aluminum, manganese, and phenol are the main toxicologically relevant substances for human and environmental health because they can alter the quality of groundwater situated under solid waste disposal areas.

Suburban Areas in Developing Countries and Their Relationship to Groundwater Pollution: A Case Study of Mar del Plata, Argentina

/ Human activities carried out in suburban areas in many developing countries are directly related to groundwater pollution. The main objective of this paper is to analyze the relationship between land use and groundwater pollution in the suburban area of Mar del Plata (Argentina). We identified three elements that are endangering the quality of groundwater: horticultural activity, urban solid waste disposal sites, and sewage disposal on land. Fifty wells in an area of 175 km2 were sampled in order to verify the impact of these problems on groundwater. All samples were analyzed for major ions, and about 30 of them for fecal coliforms and heavy metals. Nineteen samples were selected for pesticide analyses. The average nitrate content was 80 mg/liter, eight times the regional background value. Fecal coliforms were detected in 60% of the analyzed samples. Zinc content and a high Cl-/HCO3- ratio were observed in the surroundings of the solid waste disposal area. Moreover, lindane and heptachlor pesticides were detected in ten samples.KEY WORDS: Suburban areas; Groundwater pollution; Groundwater management; Argentina

Analytical Modelling Of Organic Contaminants In Leachate

Mathematical modelling is a helpful tool for predicting the hazards which arise from contaminants in leachate. These kinds of models are based on exponentially varying leachate concentration with time. In this research, a model for estimating the concentration of organics, measured as Chemical Oxygen Demand (COD), in leachates from solid waste disposal areas is developed. The model contains processes such as dissolution/dilution, mass transfer, substrate utilization, and microbial mass production. The recommended analytical model is compared with experimental data from two laboratory-scale plants. In addition, the variations of model parameters with the governing processes are determined with respect to time. Experimental data from laboratory and field studies in literature is simulated to verify the model. In order to determine some estimated parameters found by trial and error during modelling, multiple regression equations for the values from simulations are created.

Analytical Modelling of Organic Contaminants in Leachate

Mathematical modelling is a helpful tool for predicting the hazards which arise from contaminants in leachate. These kinds of models are based on exponentially varying leachate concentration with time. In this research, a model for estimating the concentration of organics, measured as Chemical Oxygen Demand (COD), in leachates from solid waste disposal areas is developed. The model contains processes such as dissolution/dilution, mass transfer, substrate utilization, and microbial mass production. The recommended analytical model is compared with experimental data from two laboratory-scale plants. In addition, the variations of model parameters with the governing processes are determined with respect to time. Experimental data from laboratory and field studies in literature is simulated to verify the model. In order to determine some estimated parameters found by trial and error during modelling, multiple regression equations for the values from simulations are created.

Radionuclide export by deer mice at a solid radioactive waste disposal area in southeastern Idaho.

Concentrations of 90Sr, 137Cs, 238Pu, 239+240Pu, and 241Am in deer mice tissues collected from a radioactive waste disposal area in southeastern Idaho were significantly (p less than 0.05) higher than those from a control area. The highest concentrations of Pu and Am occurred in pelts of deer mice inhabiting an area which had elevated surface and subsurface soil concentrations of these nuclides as compared to other Subsurface Disposal Area locations. Therefore, transuranic contamination in tissues likely originated from both soil depths. However, 137Cs and 90Sr in tissues likely originated from subsurface areas, since surface soils were below background concentrations for these nuclides. Based on a minimum of 6160 deer mice inhabiting the 36-ha waste disposal area over a 1-yr period, a total minimum inventory of 22.8 mu Ci radioactivity was contained in deer mice tissues. Of this estimate, 22.7 mu Ci activity was due to the radionuclides 90Sr and 137Cs. An estimated total of 8.4 mu Ci was transported from the disposal area in mice dispersing from the area. A calculated annual radionuclide inventory of 28.8 mu Ci in deer mice feces was deposited in and around the radioactive waste disposal area. Deer mice inhabiting the SDA are a mode of radionuclide uptake and transport; however, the environmental consequences of this transport mechanism are likely minimal. The results for deer mice, which make up 69% of the small mammal biomass, are discussed in relation to other small mammals within the disposal area. Other modes of transport associated with the deer mice, such as radionuclides in excavated soils associated with burrowing activities and predation, are also discussed.

Radiation Dose to Small Mammals Inhabiting a Solid Radioactive Waste Disposal Area

(1) Radiation dose rates received by deer mice (Peromyscus maniculatus (Wagner)) and Ord's kangaroo rats (Dipodomys ordii (Woodhouse) inhabiting a solid radioactive waste disposal area and a control area in south-eastern Idaho were determined by surgically implanting lithium-floride thermoluminescent dosimeter (TLD) packets. Fifty-three percent of the 542 and 135 TLD packets implanted in deer mice and kangaroo rats, respectively, were recovered. (2) The radiation dose rates received by animals from the radioactive waste disposal area varied from 4 to 418 000 gGy day-' (0-4-42 000 mrad day-') and were significantly (P < 0.01) higher than the dose rate of 4 gGy day-' (0-4 mrad day-') received by control animals. Doses resulted primarily from radiation from buried activation and fission products and not from radionuclides in/on tissues. (3) Ninety-six percent of the waste disposal area deer mice in the autumn-winter had radiation dose rates higher than the rates of the control animals, whereas in the spring-summer 73% of the deer mice received dose rates greater than the rates of control animals. Differences in seasonal data were probably related to increased subsurface time in autumn-winter. (4) Autumn-winter dose rates received by kangaroo rats were significantly (P < 0.05) higher than spring-summer rates and were attributed to the species entering torpor beneath the soil surface during winter. (5) Conservative comparisons between the radiation dose rates received by implanted TLD packets in individual small mammals and the potential dose rates received by individual animals on the surface of the area indicated a minimum of 49 and 20% of the deer mice and kangaroo rat populations, respectively, encountered areas of buried activation and fission waste and/or contaminated soil. (6) Data obtained provided an indirect method of measuring biological intrusion into soil covers over solid low-level radioactive waste disposal areas.

Polonium-210 in the environment around a radioactive waste disposal area and phosphate ore processing plant.

Polonium-210 concentrations were determined for soil, vegetation and small mammal tissues collected at a solid radioactive waste disposal area, near a phosphate ore processing plant and at two rural areas in southeastern Idaho. Polonium concentrations in media sampled near the radioactive waste disposal facility were equal to or less than values from rural area samples, indicating that disposal of solid radioactive waste at the Idaho National Engineering Laboratory Site has not resulted in increased environmental levels of polonium. Concentrations of 210Po in soils, deer mice hide and carcass samples collected near the phosphate processing plant were statistically (P less than or equal to 0.05) greater than the other sampling locations; however, the mean 210Po concentration in soils and small mammal tissues from sampling areas near the phosphate plant were only four and three times greater, respectively, than control values. No statistical (P greater than 0.05) difference was observed for 210Po concentrations in vegetation among any of the sampling locations.

Soda Ash Treatment of a Strontium‐90‐Contaminated Groundwater Seep

AbstractA 90Sr‐contaminated groundwater seep on the perimeter of a low‐level radioactive solid waste disposal area at the Oak Ridge National Laboratory (ORNL) was treated by burying 315 kg of soda ash in the groundwater flow path leading to the seep, and placing 45 kg of soda ash on the surface of the seep. The concentration of 90Sr in the seep water fell from an average of 7000 Bq L−1 to 900 Bq L−1 for the 90 d after burial, followed by a period of gradual rise back to pretreatment levels over the next 100 d. The electrical conductivity and pH of the seep water increased following soda ash burial, while water hardness fell. Hardness was highly correlated (r = 0.84) with 90Sr concentrations over the entire 2‐year observation period, indicating the similar behavior of 90Sr and soluble Ca and Mg. This in situ softening of, and 90Sr precipitation from, the seep water was achieved by coprecipitation of 90Sr with Ca(Mg)CO3 until the buried soda ash was depleted by dissolution in the groundwater. The soda ash treatment of groundwater seeps appears to be most practical as an interim technique for those situations requiring an immediate, but temporary, corrective action. During this limited but effective period, more permanent corrective actions could be planned at the source of contamination. The electrical conductivity, pH, and hardness of the larger surface stream, into which this seep discharges, were not affected by the soda ash burial, most likely due to the approximately 2000‐fold dilution effected by this stream.

Ecological Characteristics of Small Mammals on a Radioactive Waste Disposal Area in Southeastern Idaho

Species composition, diversity, biomass and densities of small mammal populations were examined in crested wheatgrass (Agropyron cristatum) and Russian thistle (Salsola kali) habitats on a solid radioactive waste disposal area and in native sagebrush (Artemisia tridentala) habitat surrounding the disposal area. The 15-month live-trapping study resulted in the marketing of 2384 individuals representing 10 species of small mammals. The deer mouse (Peromyscus maniculatus) was the most common rodent in both disposal area habitats and the adjacent sagebrush habitat; Ord's kangaroo rat (Dipodomys ordii) was also an abundant rodent in all vegetation types. The montane vole (Microtus montanus) was common only in crested wheatgrass stands on the disposal area. Although the adjacent native sagebrush habitat had the highest species diversity and the Russian thistle habitat on the disposal area had the lowest, the total rodent density was not significantly different among the three vegetation types. Crested wheatgrass within the disposal area contained the largest rodent biomass throughout the study, in part due to an increasing M. montanus population. The peak small mammal biomass of 5000 g/ha in creasted wheatgrass and sagebrush habitats was considerably higher than previously reported for similar habitats. Differences in diversity and biomass between the disposal area andmore » surrounding native habitat are most likely related to differences in soil compaction and vegetation between these two areas.« less

Small Mammal Soil Burrowing as a Radionuclide Transport Vector at a Radioactive Waste Disposal Area in Southeastern Idaho

AbstractDuring 1978 and 1979, small mammals excavated a total mass of 12,450 kg soil to the 36‐ha surface of a solid radioactive waste disposal area in southeastern Idaho. Elevated concentrations of 238Pu, 239,240Pu, and 241Am were detected in excavated and surface soils in the waste disposal area. The inventory of 66 µCi (90Sr, 137Cs, 238Pu, 239,240Pu, and 241Am) transported to the surface of the waste disposal area by small mammal excavations was significantly (P ≤0.05) greater than the 20 µCi estimated to occur in excavated soils at a control area where no radioactive waste was disposed. Seventy‐seven percent of the radioactivity in soil excavated to the surface of the waste disposal area by small mammals was 238Pu, 239,240Pu and 241Am; 98% of the radioactivity in excavated soil in the control area was 90Sr and 137Cs. Small mammal burrowing is a mode of transuranic radionuclide transport to the surface of the waste disposal area; however, the total amount of plutonium in excavated soils was only 0.05% of the amount estimated to occur in waste disposal area surface soils in 1974.

Movements and Radionuclide Concentrations of Sage Grouse in Southeastern Idaho

Movements and radionuclide concentrations of sage grouse (Centrocercus urophasianus) summering near nuclear facilities on the Idaho National Engineering Laboratory in southeastern Idaho were studied from 1977 through 1980. From 10 July through 7 September, 95% of all locations (N = 131) of radiomarked grouse were within 2 km of their feeding areas on lawns surrounding the facilities. During October and November, 82% of all radiolocations (N = 22) were greater than 2 km from these areas. The maximum 1-way movement to winter range was 81 km. Radionuclide concentrations (primarily radiocesium) were higher (P = 0.05) in sage grouse summering near a facility with liquid radioactive waste storage than in grouse summering near a solid radioactive waste disposal area or in control areas. The short biological halflife of the ingested radionuclides and the timing of sage grouse movements from summering areas reduced any potential radiation dose to a person consuming 1 of these birds. J. WILDL. MANAGE. 47(1):169-177 Radionuclides are similar to other environmental pollutants because they can enter biological cycles and may pose a danger to components of these cycles, including wildlife and man (Woodwell 1967). The transport of radionuclides from disposal sites by wildlife has been investigated (Brisbin et al. 1974, Straney et al. 1975, Cadwell et al. 1979, Springer 1979, Halford et al. 1981); however, much of this research has dealt with waterfowl or mammals. Sage grouse are attracted to nuclear facilities on the Idaho National Engineering Laboratory (INEL) in southeastern Idaho (Connelly 1982) by an abundance of forbs and free water during the summer. Some birds move off-site just prior to or during the hunting season. The objectives of our study were to: (1) document the number of sage grouse and their residence time at INEL facilities, (2) define sage grouse movement patterns away from INEL facilities, (3) document the kinds and amounts of radionuclides accumulated by grouse summering near INEL facilities, and (4) calculate the potential dose commitment to a person consuming a sage grouse shortly after it left the vicinity of an INEL nuclear facility. This study was supported by the Office of Health and Environmental Research, U.S. Department of Energy. Technical assistance was supplied by the Idaho Department of Fish and Game. We thank all of the individuals from the above agencies who contributed to this study. We are especially grateful to W. J. Arthur and I. J. Ball for administrative guidance, advice, and field assistance. I. J. Ball, R. J. Jonas, J. M. Peek, and V. Schultz reviewed earlier drafts of this paper. C. Braun and 2 anonymous referees also provided helpful comments on this manuscript.

Hydrologic factors and90Sr transport: A case study

Lack of runoff control is probably the most important potential source of problems in the operation of solid, low-level radioactive waste disposal areas. Solid waste disposal area (SWDA) 4 at Oak Ridge National Laboratory is an example of the combined effects of hydrologic factors and burial ground operations on radionuclide transport. Results from a study of90Sr transport at SWDA 4 show that both surface water and groundwater flows are important runoff control considerations and may vary in relative importance over an extended period of time. For the area studied, it is currently estimated that at least 80% of the90Sr transport is directly related to surface runoff. Therefore, it is concluded that the key to remedial action at SWDA 4 is to control surface runoff.

Chemical Treatments of Soil to Decrease Radiostrontium Leachability

AbstractThe leachability of radiostrontium from radioactive waste and through soil is one of the most salient problems with shallow‐land burial as a disposal method. The continuous leaching of buried waste at the Oak Ridge National Laboratory (ORNL), for periods up to 30 years, by lateral ground water flow has led to the contamination of surrounding soils and streams with 90Sr. The goal of the present investigation was to evaluate methods to effect either the in situ fixation or reduced leachability of 90Sr in soil. Small columns of three soils, collected from the solid waste disposal areas at ORNL, were labeled with 85Sr as a convenient tracer for 90Sr. After this labeling, but prior to leaching, the soil columns were percolated with equivalent amounts of sodium salt solutions of hydroxide, fluoride, carbonate, phosphate, silicate, or aluminate. Leaching was then initiated with 0.1N CaCl2 which was selected to qualitatively simulate ground water which contains Ca as the dominant dissolved cation. With two soils, high in indigenous exchangeable Ca2+, only 30–35% of the 85Sr could be leached from the carbonate‐treated columns. Presumably, the 85Sr was coprecipitated with the nascent CaCO3 formed during this treatment. In contrast, &gt;98% of the 85Sr was readily leached from all untreated soils. Other anions fixed variable but generally less 85Sr than the carbonate treatment. Thus, sodium carbonate appears to have a potential application to immobilize 90Sr in situ in contaminated soil.